Rotary take-up for sewing machines



Aug. 11; 1925. 1,549,081

. R. K. HOHMANN ROTARY TAKE-UP FOR SEWING MACHINES Filed Oct. 29, 1921 3Sheets-Sheet 1 Au 11, 1925. I

1,549,081 R. K. HOHMANN 1 v ROTARY TAKE-UP FOR SEWING MACHINES I FiiedOct. 29, 1921 ssneets-snet 2 I 8 VENTOI? 1% M [MM Patented Aug. 11,1925.

omrsn STATES PATENTOFFHIC'E.

RICHARD K. HQHMANN, OF PERU, INDIANA, ASSIGNOR TO .HOHMANN SEWING MA-CHINE COMPANY, OF PERU, INDIANA, A CORPORATION OF INDIANA.

ROTARY TAKE-UP roa SEWING macnmns.

Application filed October 29, 1921. Serial No. 511,407.

o all whom it may concern.

Be it known that I, RICHARD K. Hon- MANN, a citizen of the UnitedStates,'and resident of Peru. in the county of Miami and State ofIndiana, have invented certain new and useful Improvements in RotaryTake-' Ups for Sewing Machines, of which the following is aspecification.

The general object of my present invention is to provide improved meansfor feeding and drawingthe thread back and forth through the eye of theneedle of a sewing machine as required to provide the needle thread usedin the needle thread stitches,

T and to form and draw up the thread loops made in the stitch formingoperation.

My invention comprises 'a-novel rotary take-up mechanism proper, whichpreterablv is associated with provisions for automatically adjusting thethread take-up movement to compensate for variations in the thickness ofthe material sewed, and preferably also, is associated with means fordrawing the thread from the supply spool as required without subjectingthe take-up mechanism to the variable pull of the needle thread requiredto draw the thread ofi' the supply spool, and with means-for prevent ingthe thread from collecting in the takeup mechanism in case the threadbreaks at the work. My novel take-up mechanism is distinguished fromother rotary take-up mechanisms heretofore devised by a specialarangement of thread guides and rotatable thread deflecting studswhereby a relatively large take-up effect is obtained with a relativelyshort amount of thread in the takeup mechanism, 'and whereby the threadloops formed may readily lee-expanded and con-- tracted at the properstages of the stitching operation. The comparative shortness of theportion of the thread in the take-us mechanism at any one time makes thethrea relatively easy to control in the different stages of thestitch-forming operation, and minimizes the liability to thread breakageand reduces thetrouble resulting from such breakage.

My invention was primarily devised for use inhigh speed rotary hooksewing machines in which the thread bobbin is several times larger thanthose now in use, and the size of the thread loops passed around thebobbin and it'sjcarrier are correspondingly increased.

The various features of novelty which characterize my invention arepointed out with particularity in the claims annexed to and forming apart of this specification.

' For a better understanding of the invention,

however.

, .and its advantages, reference should be had to the accompanyingd'raw- A ings in which I have illustrated a preferred form of embodimentof my invention.

Of the drawings:

Fig. 1 is a. side elevation, with parts broken away and in section of a.sewing machine head; I

shown in Fig. '1;

Fig. 3 is a view taken similarly to Fig. 2

Fig. 2 is an end elevation of the apparatus but showingtheparts indifferent relative positions Fig. 4 is anend elevation of a portionofthe machine with some parts removed;

Fig. 5 is a section on the Fig. 2;

Fig. 6,is a side elevation of'the take-up mechanism proper;

Fig. is an end elevation ofa portion of the thread -take-up guide; and

is a section on the linev 8-8 of In the drawings I have shown myinvention embodied in a'sewing machine comprising a table or base A andan arm A of the u'sualiform. J ournalled in the arm A is a main shaft Bwhich comprises a crank portion B through which the usual needle bar A.C is reciprocated by the connecting rod 0'.

Mounted in the sewingmachine head is the usual presser ba-r D whichcarries the presser foot D and is normally depressed by a. spring in theadjustable housing D Beneaththe table- A-is the looper shaft E driven intimed relation withthe main shaft B, as by belt 1B which runsover'pulleys which are carried by the two shatts and are ordinarily so"relatively proportioned that the looper shaftE will make two revolutionsfor each revolution of. the shaft B. At its' I front end the shaft Ecarries a looptaker F provided'with a beak or hook F fordrawingaloop'inthe needle thread and carrying v the loop about thenon-rotatable. bobbin housing or carier G. I represents the. usualtension device through which the. needle thread passes from the supplyspool to "the take-up mechanism'and needle, and D represents a leverconnected to the presser bar D. for actuating the tension device I torelease the thread when the presser bar is raised to permit theinsertion and removal of the work. In so 'far'as above described thesewing machinemechanism may be, and

' isshown asbeing, like those now known and members and rotate'withtheshaft B. As shown the engaging t e rear in general use except thatthethread carrier and looptaker are shown as larger in diameter than insewing machines in common use.

My improved take-up mechanism, in the form shown, comprises two coaxialdisc like 'and: K which are secured to,

disc K is secured to the end of the shaftB by screws K, and theidisc Kis spaced away from and is connected to the disc K by thread-engagingstudsK and K. The stud K is located adjacentthe periphery of the discswhile "the stud K, which, having reference to the direction of rotationof the discs, is angularly back from the stud K, and is intermediate theaxis of the shaft.

I stationary thread guide back of the discs K and .K which, as shown,comprises'a dish sha ed memberL mounted int-he arm A,

-an a disc-L, secured to the member L but spaced away from thelatter attheir under 5 sides to provide a thread channel L 'open at.

its lower edge and the upperedge ofwhich is represented in Fig; '2 bythe dottedline L. The front face of the disc Lis spaced away from thediscK sufliciently to avoid fri'cthe portion of the-needle threadrunning tional contact with the latter', ="and the disc 7 K ispreferably provided witha flange or V rib K at its rear side to preventthe portion of the thread which should'pass'through the channel L fromentering the space between the discs L and 'K fl' The disc L has 'itsedgebevelled, as indicated at L, andthe b0 y portion L, of the member Lis tapered t guide the thread into theehannel L54, a

. The means shown foricompensating';for.

the thickness of the goods sewedcomprises a 4 lever M provided with aneye M nigh-1116 needle thread at one. end, and. ivotally ;con'-"nected-at its op osite end to t e'sewingfmachine head as y means ofthe-screw M Intermediate its ends the lever rM. is "pivotally connectedto the presse e) I) the connection being formed, as shown, by stud DMcarried by a bracket D which is adjustably secured to the presser bar Das by the clamping screw D*. The stud DM passes through a slot formed inthe lever M. With this arrangement, as the presser bar D is raised orlowered by the engagement of the presser foot D with the top of Work ofgreater or less thickness, the thread eye M of the lever M iscorrespondingly raised and lowered through distances several times thosethrough which the presser bar itself is moved. v

; To pull the thread off the needle thread supply spool- (not-shown) asrequired, and thereby prevent the. operation of the takeup mechanismfrom being affected by .the

variable resistance of the thread as it is pulled off the'spool, Irovidea thread pul-- ler to act on the threa between the supply spoolandtension. The thread puller is in the form of a bent arm N carried bythe needle bar C and projecting through the slot A in the frame arm A.The arm N is formed with a fork N" at its outer and upper end which, atthe end of each upstroke of the needle bar, engages and formsa bight inthe portion of the needle thre'ad T running between a pairof threadguide eyes 0 "and O secured to the arm A'.-

The needle thread T, in the construction illustrated, runs from thesupply spool (not shown) through a'thread guide. 0 to the thread guidesO and O and thence to the tension device I from which it passes intothe. eye M of the lever M. From the eye M the thread passes backof thefinger H at from the eye M to the guide .0 is engaged on its-upper sideby the take-up stud K and deflected away from the straight line betweentheey'e M and the guide 0 during a portion of each rotation of thedriving shaft, and the portion of'the thread runnin from the guide 0? tothe guide 0 is en age at its under side by the studs K" and 5 in{varying degrees aslthe studs .travel around their orbit and therebydeflected away from the straight line betweengthe guides '0 and 0 Themaximum'aggre'gate deflection of the thread extending from the lever e eM to the guide 0' is reached at the comp etion of each stitch when;.the;a pparatus is in the position shown in Fig. 2. As'the parts movefrom the position shown inlii'g. 2 in the succeeding stitch formingoperation, the thread blght engaged by the stud K and that'e'ngaged bythe stud K": are each permitted to shorten as the needle descendsthrough the workand the needle thread is engaged below the work by thehook F and drawn into a loop which is-carried about the bobbin car-.

rier. Fig. '3 represents the condition of the apparatus when the looppassed about the.

bobbin carrier is fully distended. In'Fig. 3 the needle bar is a littlebelow the top of its stroke as is the case also with the apparatus inthe position shown in Fig. 2. In moving 7 from'the position shown inFig. 2 into that shown in Fig. 3, thestnd K quickly passes out ofengagement with the needle thread and does not engage the latter untilafter the apparatus has movedfrom the ---position shown in Fig. 3 towardthat'shown in Fig. 2. As shown, however, the portion of the threadextending between the guide and the guide 0 is constantly engaged by oneor other or both of the studs K and K, which thus exert a controllinginfluence 'on' the thread, while the bobbin encircling 100%; are beingformed as well-as when they are ing.

, drawn up. 1 w

Distinguishing characteristics of my takeup' mechanism are therelatively large amount of thread take-up movement obtain a'ble with a.rotary take-up mechanism trgiven diameter, and the small length orthread in the take-up .me'chanism between the eye M and guide 0. at anytime in comparisionwith the amount of thread take-u movement obtained.YA reduction in di amet'er of the takeup mechanism is of greatimportance in a high speed sewing machine not only because it'reducesthe bulk of the take-up" mechanism and the. centrifugal stresses acting.ongthettakeeu-p mechanism -proper, bu't alsobecause. it' facilitatesthe manipulation of thethread, reduces the ten- 'dency thread breakageand minimizes the annoyance and trouble produced incase .of threadbreakage which inevitably occurs pf lrofn time to time in the operationof the 1 sewing machine. The" location of the guides 50 M, 0' and 0relative to one another and to the y of movement of the deflecting studsK the latter, all contribute to thef relatively great take-up movementobtainable with a take-up of givengdiam'eter, and to make the amount ofthread in the take-up mechanismat one time relatively small. T 9 Whenthe needle thread; breaks -in sewing -it ordinarily breaksjat thei-jwork," andwith ordinary,rotaryv take-up mechanisms sueh breakage is'apt1 ',;tol -;result in annoyaiieeanddelay as .well as thread waster-because/"0f of r esus thread.

aboutthe thread'deflecti-ng studs or other rotating portions of the takeup mechanism.

- presser foot pr "amount of thread. take"? thick goodsgrthangj ivith' t1n amount of makeu 'producedbythe take-up and K, and the relativelocation or Toavoid this trouble with the mechanism. :shown Ihaveprovided a thread catcher which will engage thepo'rtion of the thread inthe take-upiriechahmm adjacent the eye BIC- 111d hold it so that thestud K will break thethread at this int whenever the portionof thethread1n the channel L is allowed, to slacken-as it does when the threadbreaks at the work. In the construction illustrated I form .this threadcatcher by cutp'ing groove between the projection L anl the .under edgeof the hook L". -Wi th this arrangement' when the thread passing throughthe channel L? is permitted to slacken as it does when the needlethread'breaks at the 5 ting a notchLEjn the disc L? .to provide a r hook,Lt-atj theperiphery of the disc L adjacenttheey'e M",;a'nd by extendinga rojeo' 'tion. L from' the plate Linto the note L so flaisfto formacrotch or V-shaped thread grip-' so l work, the take-up, stud K almostinstantly,

that is, within: a few turns of the takeup mechanism, works the slackthread into a position-in which the thread is caught in the any threadatall is drawn into theltak'e-u When working witl i relatively thick worki the presser foot D is "maintained higher above the table Athan whenworking on thin work. The chalages in elevation of the magnified.changesin elevation of the eye guide M of the lever M. -With: thearrangement shown, any; upward mo v efme'ntof the eye guide M'.increases and. any downward movement oi thefeye "decreases the extent ofdeflection and consequentlyetheamountof thread take up stud K thusautomatically provid ng emissary-with good'l, Th

theg greater uces corresponding but mechanism disclosed can be adjustedby rais- I ing and lowering the 'Tbracket which is adjustably clampedtethe presseribar Dxand is y pivotally eonnected to'the lever M.

While-in accordance with the provisions of the statutesIy-haveillustrated anddescribed the besfig'iormlof my invention nowknown to.

me, it will apparent'to those skilled'in the artfthatchaiiges'ma 'bemade in the form of {the :aapparatua. disc sed flwith'outldeparting'-lfrom thev spirit of my inventlonT asset forth in the appended claims,and that certain fea- --tures ofm.y invention may-sometimes be used.Qeadvantagewithout a corresponding use of other features.

Having now de'scribed my invention,what

; I{ ,claim as newand desire to secure byImters Patent, is

1. In a rotary take-up mechanism the combination with a rotating memberof a thread deflector carried thereby, a second thread deflector carriedby said member and displaced relatively to the first deflector axiallyand backward having reference to the'rotative movement of said memberand three nonrotating thread guides outside of the orbital paths of saiddeflectors and located one about 1 90 in advance of the second and thethird in advanceof said one deflector and less than 180 in advance ofsaid second deflector having reference to the rotative movement of saidmember,said guides and deflectors being relatively disposed and adaptedfor the passage of the thread toward the needle from said third threadguide to said second guide beneath and in the path of said seconddeflector and from said second guide to said first guide over and inengagement with the first mentioned thread deflector.

2. In a rotary take-up mechanism the combination with a pair ofangularly and axially displaced rotating thread deflecting studs, of athread guide at one side of the take-up mechanism, a second guide at theopposite side of the take-up mechanism and a third guide below thetake-up mechanism with the needle thread passing between saidfirst andsecond guides in position to be enaged by one of said studs and passingfrom t e second guide tothe third guide in position to be engaged by theother of said studs, and means for adjusting the relative angularpositions of said guides to vary the extent of the take-up.

3.- In a rotary take-up mechanism, the combination with a threaddeflecting stud moving in an orbital path, of a stationary thread guideformed with a kerf-like thread channel located within said path, andmeans for holding the thread insaid channel with its projecting portionsprojectin therefrom across the path of movement of the stud.

4. In a rotary take-up mechahism the combination with a rotating diskand athread deflecting studcarried thereby of a stationary thread guideformed with a kerflike thread channel within the path of 'rotationoftsaid stud, means for holding the thread in said'channel with its endsprojecting across the path of movement of said stud, said disc being,provided with; a peripheral rib on its face adjacent said guide toprevent the thread from working into the space between the guide anddisc.

5. In a sewing machine, the combination with ,a presser bar and a rotarytake-up. mechanism comprising a thread deflecting stud travellin in anorbital path of means actuated by t e adjustmentof the presserbarresultin from difli'erences in work thickness for a justing. theamount of thread take-up, said means comprising a lever piv--.

oted to a stationary support and connected engaged by said stud, oneof'said to said presser bar to be oscillated relative to said supportwhen the presser bar is adjusted, and provided with a guide eye for thethread, and a second thread guide to which the needle thread portionengaged by said deflecting stud passes from said guide eye, said guideeye and second thread eye being horizontally displaced in opposite toaccommodate differences in work thickness' will move the line connectinsaid thread guides toward or away from t e axis of rotation of said studand thereby eifect a compensating adjustment in the amount of threadtake-up.

7. In a sewing machine having a rotat ng take-up, the combination with arotating thread deflecting stud, of guides between which the threadpasses in position to be being adjustable to move the threa runningbetween the guides toward and away from the axis of rotation of saidstud and thereby vary the amount of thread deflection produced bysaid'stud. b

8. "n a sewing machine, comprlsing a 7 thread tension device, a needlebar and needle, and a take-up mechanism interposed between the tensiondevice and needle, of a thread puller, connected to theneedle bar andengaging the thread at the opposlte side ides of the tension from thetake-up mechanism and pulling the'thread'on the rising movement of theneedle bar.

9. In a rotary hook mechamsm for sewing machines, having a. threadtension, the

combimation with a rotary take up mechanism comprising a stud travellingin an orbital path, a thread guide to w 1ch the needle t read .passes.from said tension dej vice, a second thread guide to which the needlethread passes from the first mentioned guide, both of said guides lyingwithout sa1d path but so located relatively thereto. that. the threadportion running between said guides when under tension assumes a'POSItlOH intersecting the movement of said stud except w gaged by saidstud, "and thereby deflected path of en enfrom sa1d position, and athread catcher which is located within said path at the oppo'site sideof said position from that to-v ward which the stud deflects the thread,and

by which the thread portion running between 'said guides is caught whenthe normal thread tension is released by the breaking of the threadbetween the take up and the work, whereby when the thread is caught bysaid thread catcher it is engaged by said stud between the threadcatcher RICHARD K. HOHMANN

